1. Field of the Invention
This invention relates to medical IV administration line connectors. More particularly, this invention relates to a needleless medical IV quick-connect/disconnect assembly for attaching and detaching a patient to and from an IV system.
2. State of the Art
Intravenous therapy has a long history of use in supplying patients with medicament, nourishment or fluids. One of the problems associated with intravenous therapy of ambulatory patients is that the patient cannot be easily disconnected from and reconnected to an intravenous administration line for short periods of time. To safely and easily disconnect the patient for even a short period of time requires the assistance of skilled medical personnel. The ambulatory patient is often required to be attached to the intravenous system and must wheel a stand holding the IV liquid supply wherever the patient goes. Being restricted in this manner can cause the patient to forgo activities of short duration that would be beneficial to the patient.
It is often necessary for hospital staff to move patients from location to location within the hospital in order to perform tests and certain medical treatments. It is not necessary or desirable to have the patient hooked up to the intravenous system during some of these activities. Removing a patient from an intravenous system and re-establishing the patient on the system takes a substantial amount of time even for a medical professional skilled in the techniques of intravenous therapy. With hospital costs rising dramatically there is considerable advantage in a connector device that allows the medical staff to be able to quickly and safely connect and disconnect a patient from an intravenous therapy administration line while expending a minimum amount of time in doing so.
The prior art has addressed some of the above stated problems. For example, U.S. Pat. No. 4,511,359 issued to Vaillancourt describes a three-part sterile dialysis connection device for home use. The three parts are a male connector which terminates in a catheter tube; a female connector with a hollow needle secured in place and terminating in a flexible tubing; and a molded septum assembly. Vaillancourt places the molded septum assembly in the receiver end of the female connector. The female connector is then slid over the male connector, thereby pushing the septum assembly into place between the male and female connectors, and into friction fit with the male connector, and also causing the sharpened needle in the female connector to pierce the molded septum assembly. The hollow needle provides a path for fluid flow between the two connector parts. When the male and female connectors are separated, the needle is removed from the self-sealing septum, and the septum assembly remains with and covering the male connector because of its friction fit therewith.
Another three-part home dialysis connection device is described in U.S. Pat. No. 4,810,241 issued to Rogers which provides a sterile connection by mechanical and chemical means. The three parts include two connectors, one attached to an influent tube and the other to the catheter tube, and a cylindrical shaped tube in which there is highly absorbent material saturated with antiseptic. The two connectors in turn connect one to each end of the cylinder. As the end connectors are introduced into the central cylinder connector, they are sterilized by the antiseptic in the cylinder and remain in antiseptic contact during the entire time they are being used for dialysis. A sterile environment is maintained on the catheter tubing side of the IV system only for so long as the catheter side tubing is in the connector cylinder. Care must be taken not to let the disinfectant in the cylinder dry out or evaporate.
A somewhat different solution to the problem was taken by U.S. Pat. No. 4,559,043 issued to Whitehouse, et al. which provides a four-piece assembly including a distal connector, a proximate connector, a septum fitting between and held in place by the distal and proximate connectors, and an adapter with a through bore able to accept a hollow needle, the adapter being used in conjunction with the proximate connector. A hollow needle attached to a standard luer extension T which connects to the adapter is pushed through the adapter needle bore and pierces the septum which is held between the proximate and distal connectors, thereby establishing fluid flow. When the hollow needle attached to the luer T is removed, the septum is sealed, but the needle is exposed, presenting a needlestick hazard.
While these devices of the prior art may be effective for their particular purposes, the requirement for a simple, low-cost, quick-connect/disconnect safety assembly is not filled. The prior art does not show a device which has all of the virtues in a single device of being simple and inexpensive to manufacture, providing standard means such as luer fittings for attachment to other devices, and providing means for shielding the needle after use to prevent accidental needlesticks.
My prior U.S. Pat. No. 5,139,483 (the complete disclosure of which is incorporated herein by reference) teaches an IV quick-connect/disconnect device having molded single piece male and female connectors. The male connector has a male luer-lock on one end, a pair of outwardly extending bayonet knobs on a middle portion and a reduced diameter second end which terminates in a resilient septum. The female connector has a female luer-lock on one end and a receiving cylinder with a pair bayonet cutouts on the other; the luer-lock and the cylinder being separated by a wall through which a hollow needle extends that has been insert molded in the wall. The male and female connectors are mated by sliding the reduced diameter second end of the male connector into the receiving cylinder of the female connector, with the bayonet cutouts of the female connector serving as a track for the extended knobs of the male connector. The connectors are locked into place by bringing the male connector as far forward as possible, and then rotating the male connector such that extending knobs move past a restriction in the cutout and click (lock) into place.
This arrangement overcomes many of the disadvantages of the prior art, but it still has its drawbacks. The female connector is fragile due to the bayonet cutouts and these cutouts form a ragged end surface of the female connector when the connectors are uncoupled. The cut outs can actually catch or snag surgical gloves or other medical equipment. Similarly, the bayonet knobs of the male connector present a ragged surface of the male connector when it is uncoupled from the female connector. Moreover, the bayonet knobs on the male connector sometimes extend slightly beyond the outer surface of the female connector when the connectors are coupled. The extended bayonet knobs of the male connector result in a less than totally smooth surface and this surface can catch, snag and cause tears in surgical gloves, etc. Unfortunately, there is no easy way to avoid this problem because insert molding the needle in the female connector substantially requires that the bayonet cut outs be located on the female connector rather than on the male connector. Indeed, manufacturing considerations have limited the features of these connectors in several ways and the provided features have dictated some inconvenient manufacturing steps. For example, the resilient septum at the second end of the male connector covers a portion of both the inside and the outside wall surface of the second end and is held in place by a thin plastic shrink band. This is not an ideal configuration since the septum and the shrink band are exposed to wear and can be torn. Additionally, the female connectors may carry either an 18 gauge or a 20 gauge needle depending on the type of fluid to be delivered through the connectors. There is presently no simple way of distinguishing the larger gauge needles from the smaller gauge needles without direct comparison.
The parent of this application solves many of the aforementioned disadvantages by providing a suitably molded single piece male connector and a two piece female connector. The male connector has a male luer-lock on one end, one or more inwardly extending bayonet recesses on the surface of a middle section of reduced diameter and a further reduced diameter second end with a cold rolled edge which encloses a resilient molded septum or the like. The first piece of the female connector has a female luer-lock on one end and a first portion of a receiving cylinder on the other, the luer-lock and the first portion of the cylinder being separated by a wall through which a hollow needle extends that has been insert molded or bonded in the wall. The second piece of the female connector is the second portion of the receiving cylinder which is sonically welded to the first piece. The second piece has one or more inwardly extending knobs on-its inner surface which are arranged to engage the inwardly extending bayonet recesses of the male connector when the reduced diameter second end of the male connector is placed in the receiving cylinder of the female connector. The pointed end of the hollow needle is located in the second portion of the receiving cylinder. The outside cylindrical surfaces of both the male and female connectors (both before and after mating) are smooth with no projections that can catch or snag other medical equipment.
In using the male and female connectors, an IV administration line with a male luer-lock or luer-slip is inserted into the female luer side of the female connector, while an IV winged needle or catheter device that is connected directly to an extension line or the like which terminates in a female luer-lock or luer-slip is connected with the male luer-lock or luer-slip of the male connector. The male and female connectors are mated by sliding the reduced diameter second end of the male connector into the receiving cylinder of the female connector, with the recesses of the male connector serving as a track for the inwardly extending knobs of the receiving cylinder of the female connector. As the male connector is slid forward, the needle in the female connector pierces the resilient septum which permits the flow of liquid through the septum via the hollow needle. The connectors are locked into place by bringing the male connector as far into the female connector as possible, and then rotating the male and/or female connector such that the knobs on the female connector move past restrictions in the recesses in the male connector and both connectors click (lock) into place. Quick release is obtained by rotating the male and/or female connector in the opposite direction and pulling the male connector straight out relative to the female connector. When the male and female connectors are separated, the needle in the-female connector is withdrawn from the self-sealing resilient septum held in the reduced diameter second end of the male connector.
Despite all of the safety features in my earlier patent and in the parent of this application, both devices utilize a needle to pierce a septum. It is currently appreciated that a completely "needleless" IV line connector would offer substantial advantages.
Needleless valves are not unknown in the art of IV administration. U.S. Pat. No. 4,683,916 to Raines, e.g., discloses a normally closed automatic reflux valve for use in the administration of fluids and medicinal liquids in medical environments. The valve includes a two-part body having a male luer lock on one part and a female luer lock on the other part. Both parts also have cylindrical container portions which, when connected, restrain a flexible valve disk. A pointed triangle in one of the cylindrical container portions supports a central area of the disk which in turn is under pressure from a traverse bar mounted in the other cylindrical portion. The pressure between the triangle point and the bar generally is sufficient to restrain the disk against sideways movement. A small plastic plunger having an open cylindrical end and a pair of dependent legs is slidably mounted on top of the disk and extends into the female luer lock. When the tip of a syringe or male luer connector engages the open cylindrical end of the plunger and presses it inward, the disk is flexed against the triangle to open the valve. When the injection device or male luer connector is removed, the resiliency of the disk closes the valve. While Raines' valve has certain advantages, it does not work well. It is easily clogged, especially when glucose solutions are being fed through the valve, and the resiliency of the disk is often insufficient to provide a sealed closure when the male connector is removed.
U.S. Pat. No. 4,908,018 to Thomasen discloses a method and apparatus for injecting fluids into an IV line. Thomasen's device consists of a cylindrical member having a female luer coupling at one end, an annular shoulder, a poppet with an imperforate top engaging the shoulder, and resilient buckling legs biasing the poppet against the shoulder. When a male luer is coupled to the female luer coupling, the poppet is unmoved. When fluid is forced through the coupling, however, the poppet is moved away from the shoulder under the pressure of the fluid. Thomasen's device has several disadvantages. First, it requires that the fluid pressure and the resiliency of the buckling legs be properly matched so that the valve opens and closes as desired. Second, Thomasen's device requires that fluid be injected under pressure before the valve opens. Its use, therefore is limited for injection only, and it cannot be used to withdraw fluids from an IV line.
U.S. Pat. No. 5,230,706 to Duquette discloses a bi-directional valve assembly used in needleless injection or infusion ports. Duquette's valve assembly includes a valve body containing a valve port, a valve plunger having a sealing means, and a spring. The spring urges the valve plunger towards the valve port so that the sealing means seals the valve port. The valve port is disclosed as a female luer-slip and the valve plunger has a stem which enters the luer slip when the valve is sealed. Insertion of a male luer-slip into the valve port engages the stem on the plunger and moves the plunger against the spring to open the valve. Upon removal of the male luer-slip, the spring urges the valve back into the sealing position. Duquette's valve assembly solves many of the problems addressed above. However, it requires at least four parts (valve body, spring, plunger, and valve port) and the assembly of the pieces is difficult since there appears to be no convenient way to connect the valve port to the valve body so that a fluid tight coupling is effected.
U.S. Pat. No. 4,681,132 to Lardner discloses a check valve having a preset cracking pressure. The check valve is assembled from three parts: a valve body, a valve element and a plug. The valve body is sleeve-like having a central axial passageway defining an input and an output and a frustroconical valve seat converging towards the input. The valve element has a stem, a frustroconical seat converging towards the stem, and a resilient annular wall extending from the seat and capable of flexing when pressure is exerted on the stem. The plug is an annular ring which is engagable in a corresponding annular slot formed in the output portion of the valve body. The valve element is inserted into the valve body so that its stem enters the input and its seat abuts the valve body seat. The plug is inserted into the annular slot in the valve body and thereby holds the valve member in the valve body with respective seats in sealing engagement. The valve is opened by applying fluid or mechanical pressure at the input onto the valve element stem. The axial length of the plug determines the amount of compression on the resilient annular wall of the valve element and thereby defines a cracking pressure necessary to open the valve. While the check valve disclosed by Lardner is relatively simple and easy to assemble, it is not readily adapted to use in an IV quick- connect/disconnect assembly. Although the input of Lardner's check valve may serve as a fluid coupling, Lardner does not provide any fluid coupling device at the output of the check valve. Moreover, to do so would add more components to the valve defeating its simplicity and ease of assembly . Furthermore, if Lardner's valve were used in an IV Y-injection port, assembly would be quite difficult in that the insertion of the plug in such a configuration is nearly impossible. In addition, in order to insert the plug in Lardner's check valve, either the output portion of the valve body or the plug itself must be resilient. Therefore, there is never any positive locking of the plug in position and it is always possible that the plug will pop out of the output of the valve body given sufficient force applied at the input of the valve body.